Help with fare codes please.

Am i right in thinking that O fares are the cheapest in economy? Also, if L fares are being offered, does that mean that O have sold out, or is this something that VA can alter as they see fit.
Travelling 10/05, back 31/05/13. ( Man-Mco). We usually book much further in advance, but this is an additional trip to celebrate our wedding anniversary, so admittedly, time may well play its part. At the moment, economy fares are coming out at £806 p.p, which seems quite high, but i can't see this altering, unless anyone has a crystal ball and knows any different. Thanks in advance
Travelling 10/05, back 31/05/13. ( Man-Mco). We usually book much further in advance, but this is an additional trip to celebrate our wedding anniversary, so admittedly, time may well play its part. At the moment, economy fares are coming out at £806 p.p, which seems quite high, but i can't see this altering, unless anyone has a crystal ball and knows any different. Thanks in advance
